This invention relates generally to the field of closure structures, and more particularly to the field of closure structures for use with refrigerator or freezer units. The invention further relates particularly to the field of closure structures which are doors in walk-in freezer or refrigerator units. Even more particularly, the invention relates to the field of closure structures able to be retrofitted into existing freezer or refrigerator units, whereby a smaller or damaged closure assembly can be replaced by the invention.
Walk-in freezer or refrigerator units are large, enclosed spaces used for storage of perishable items. In many situations, pallet jacks or other means of transporting pallets of stored goods are used to put in or remove the goods from the freezer or refrigerator units. In these situations, it is necessary to have a threshold flush with the inner and outer floors. The standard doors built into the freezer or refrigerator units are too small to allow easy maneuvering of the pallet jacks, with the result that the doors and frames are easily damaged and often require replacement. Typical replacement closures known in the art are units which are affixed externally to the outer wall. These units protrude into the workspace, are weak in respect to thermal barrier properties, and are easily damaged.
The replacement closures must perform the same functions as the original closures. They must maintain the temperature differential between the inside of the freezer or refrigerator unit and the outside. The closure should not allow moisture condensation to form on the exterior. The threshold of the closure must remain free of ice to prevent hazardous footing conditions. The replacement closure must be sufficiently insulated and sealed at all points to prevent thermal leakage into the walls or around the door.
The invention provides a replacement closure assembly which meets all the criteria set forth above. The invention allows a damaged door, or a too small door, to be replaced quickly and efficiently with a closure which is superior in properties to the original closure. The invention is structured in separate parts which allow it to be assembled onto the existing building wall and wall of the original freezer or refrigerator unit by cutting out a rectangular access opening of appropriate size around the original door location, or at any location where a new closure door is desired. The invention is structured such that the exterior of the door portion of the closure assembly mounts relatively flush to the original wall, while the entire unit is securely mated to the wall and an excellent thermal barrier is created.